WO2019026493A1

WO2019026493A1 - Power conversion device, motor module, and electric power steering device

Info

Publication number: WO2019026493A1
Application number: PCT/JP2018/024662
Authority: WO
Inventors: 元気堀内
Original assignee: 日本電産株式会社
Priority date: 2017-07-31
Filing date: 2018-06-28
Publication date: 2019-02-07
Also published as: US11356036B2; CN110915121A; JP7047844B2; CN110915121B; US20200195166A1; JPWO2019026493A1

Abstract

A power conversion device 1000 comprises: a first inverter 100A; a second inverter 100B; a drive circuit 440 for applying, to a low-side switch element of the first inverter, a control signal for turning on the low-side switch element when a failure has occurred on the first inverter side, and applying, to the low-side switch element of the second inverter, the control signal for turning on the low-side switch element when a failure has occurred on the second inverter side; and a control circuit 410. When failure occurs on the second inverter side, a first power supply voltage generated on the first inverter side is supplied to the drive circuit, and when failure occurs on the first inverter side, a second power supply voltage generated on the second inverter side is supplied to the drive circuit.

Description

Power converter, motor module and electric power steering apparatus

The present disclosure relates to a power conversion device, a motor module, and an electric power steering device that convert power from a power supply into power to be supplied to an electric motor.

In recent years, a machine-electric integrated motor has been developed in which an electric motor (hereinafter simply referred to as "motor") and an ECU (Electrical Control Unit) are integrated. Particularly in the automotive field, high quality assurance is required from the viewpoint of safety. Therefore, a redundant design is adopted that can continue safe operation even if part of the part fails. As an example of redundant design, it is considered to provide two inverters for one motor. As another example, it is considered to provide a backup microcontroller on the main microcontroller.

Patent Document 1 discloses a power conversion device that includes a control unit and two inverters, and converts power from a power supply into power to be supplied to a three-phase motor. Each of the two inverters is connected to a power supply and a ground (hereinafter referred to as "GND"). One inverter is connected to one end of the three-phase winding of the motor, and the other inverter is connected to the other end of the three-phase winding. Each inverter has a bridge circuit composed of three legs, each of which includes a high side switch element and a low side switch element. The control unit switches motor control from normal control to abnormal control when it detects a failure of the switch element in the two inverters. In the normal control, for example, the motor is driven by switching switch elements of two inverters. In the control at the time of abnormality, for example, the motor is driven by the unfailed inverter using the neutral point of the winding in the broken inverter.

JP 2014-192950 A

In the above-described prior art, there is a need for further improvement in control when the peripheral circuit of the inverter fails. Here, the peripheral circuit is a circuit necessary to drive the inverter, and includes, for example, a controller, a predriver, a power supply circuit, and the like described later. Failure of the peripheral circuit means, for example, failure of the predriver or the power supply circuit. In the circuit configuration of Patent Document 1, when a failure occurs in the control unit in addition to the failure of the switch element of the inverter, it is difficult to continue the motor drive.

In an embodiment of the present disclosure, a power conversion device capable of continuing motor driving using a neutral point even when a failure occurs in a peripheral circuit of an inverter, a motor module including the power conversion device, and the motor module An electric power steering apparatus is provided.

An exemplary power converter of the present disclosure is a power converter that converts power from a power source to power supplied to a motor having n-phase (n is an integer of 3 or more) windings, A first inverter connected to one end of the winding of each phase, the first inverter comprising n legs each having a low side switching element and a high side switching element, and the other end of the winding of each phase A second inverter connected to the second inverter, the second inverter comprising n legs each having a low side switch element and a high side switch element, the n low side switch elements of the first inverter, and the second inverter A drive circuit connected to the n low-side switch elements of an inverter, wherein when a failure occurs on the first inverter side of the motor, the first in- A control signal for turning on the n low-side switching devices of the motor is applied to the n low-side switching devices, and when a failure occurs on the second inverter side of the motor, the n of the second And a drive circuit for supplying a control signal for turning on the low-side switching device to the n low-side switching devices, the n low-side switching devices and the n high sides in each of the first and second inverters. A control circuit that controls the switching operation of the switch element and controls the drive circuit, and is generated on the first inverter side of the motor when a failure occurs on the second inverter side of the motor First power supply voltage is supplied to the drive circuit, and a failure occurs on the first inverter side of the motor. When none, the second power supply voltage generated by the second inverter side of the motor is supplied to the drive circuit.

According to an exemplary embodiment of the present disclosure, a power converter capable of continuing motor drive using a neutral point in the event of a failure in a peripheral circuit of an inverter, a motor module including the power converter, and An electric power steering apparatus provided with the motor module is provided.

FIG. 1 is a schematic diagram showing a block configuration of a motor module 2000 according to an exemplary embodiment 1, mainly showing a block configuration of a power conversion device 1000. As shown in FIG. FIG. 2A is a block diagram showing functional blocks of the first drive circuit 440A. FIG. 2B is a block diagram showing functional blocks of the second drive circuit 440B. FIG. 3 is a circuit diagram illustrating a circuit configuration of the first drive circuit 440A in the first peripheral circuit 400A. FIG. 4 is a schematic view showing an example of a block configuration of a power conversion device 1000 according to a modification of the exemplary embodiment 1. FIG. 5A is a schematic diagram showing a further exemplary block configuration of the power conversion device 1000 according to a modification of the exemplary embodiment 1. FIG. 5B is a schematic view showing a further block configuration example of the power conversion device 1000 according to the modification of the exemplary embodiment 1. FIG. 6 exemplifies a current waveform (sine wave) obtained by plotting current values flowing in U-phase, V-phase and W-phase windings of motor 200 when power converter 1000 is controlled in accordance with three-phase energization control. Is a graph. FIG. 7 is a schematic view illustrating states of currents flowing to two inverters at an electrical angle of 270 ° of the current waveform shown in FIG. FIG. 8 shows a block configuration of a motor module 2000A according to an exemplary embodiment 2 and is a schematic view mainly showing a block configuration of the power conversion device 1000A. FIG. 9 is a block diagram showing drive circuit 440 and functional blocks therearound. FIG. 10 is a schematic view showing a typical configuration of an electric power steering apparatus 3000 according to an exemplary embodiment 3. As shown in FIG.

Hereinafter, embodiments of a power conversion device, a motor module, and an electric power steering device of the present disclosure will be described in detail with reference to the accompanying drawings. However, in order to facilitate the understanding of the person skilled in the art, the following description may be omitted unnecessarily to avoid redundant description. For example, detailed description of already well-known matters and redundant description of substantially the same configuration may be omitted.

In the present specification, the implementation of the present disclosure will be exemplified taking a power conversion apparatus that converts power from a power supply into power supplied to a three-phase motor having three-phase (U-phase, V-phase, W-phase) windings. The form will be described. However, a power conversion device that converts power from a power supply to power supplied to an n-phase motor having n-phase (n is an integer of 4 or more) windings such as four-phase or five-phase is also within the scope of the present disclosure. .

Embodiment 1 [1-1. Structure of Power Conversion Device 1000 and Motor Module 2000] FIG. 1 schematically shows a block configuration of a motor module 2000 according to the present embodiment, and mainly shows a block configuration of the power conversion device 1000. As shown in FIG. In the present specification, for convenience of explanation, components on the left side of the motor 200 in the block diagram are denoted as a first inverter 100A, a first peripheral circuit 400A, etc., and components on the right side are a second inverter 100B and a second periphery. It is written as a circuit 400B or the like.

Motor module 2000 includes motor 200 and power converter 1000. The motor module 2000 can be modularized and manufactured and sold as an electromechanical integrated motor including, for example, a motor, a sensor, a predriver and a controller.

Power converter 1000 includes a first inverter 100A, a second inverter 100B, first to

sixth switch elements

311, 312, 313, 314, 315, 316, a first peripheral circuit 400A, a second peripheral circuit 400B, a controller 410, and the like. A power supply circuit 430 is provided.

Power converter 1000 is connected to motor 200 and connected to power supply 500 via coil 600. Power converter 1000 can convert the power from power supply 500 into the power supplied to motor 200. For example, the first inverter 100A and the second inverter 100B can convert DC power into three-phase AC power which is a pseudo sine wave of U phase, V phase and W phase.

The motor 200 is, for example, a three-phase alternating current motor. The motor 200 includes a U-phase winding M1, a V-phase winding M2, and a W-phase winding M3, and is connected to the first inverter 100A and the second inverter 100B. Specifically, the first inverter 100A is connected to one end of the winding of each phase of the motor 200, and the second inverter 100B is connected to the other end of the winding of each phase. Such motor connections are different from so-called star connections and delta connections. In the present specification, “connection” between components (components) mainly means electrical connection.

The first inverter 100A includes three legs each having a low side switch element and a high side switch element. The U-phase leg has a low side switch element 101A_L and a high side switch element 101A_H. The V-phase leg has a low side switch element 102A_L and a high side switch element 102A_H. The W phase leg has a low side switch element 103A_L and a high side switch element 103A_H.

As a switch element, for example, a combination of a field effect transistor (typically, a MOSFET) or an insulated gate bipolar transistor (IGBT) with a parasitic diode formed therein and a free wheel diode connected in parallel thereto can be used. Hereinafter, an example using a MOSFET as a switch element will be described, and the switch element may be described as SW. For example, the switch elements 101A_L, 102A_L and 103A_L are described as SW 101A_L, 102A_L and 103A_L.

The first inverter 100A includes three shunt resistors 100A_R as current sensors for detecting the current flowing in the windings of the U-phase, V-phase, and W-phase. The current sensor includes a current detection circuit (not shown) that detects the current flowing in each shunt resistor. As illustrated, for example, three shunt resistors 100A_R are respectively connected between the three low-side switch elements included in the three legs of the first inverter 100A and GND. The resistance value of the shunt resistor is, for example, about 0.5 mΩ to 1.0 mΩ.

Similar to the first inverter 100A, the second inverter 100B includes three legs each having a low side switch element and a high side switch element. The U-phase leg has a low side switch element 101B_L and a high side switch element 101B_H. The V-phase leg has a low side switch element 102B_L and a high side switch element 102B_H. The W phase leg includes a low side switch element 103B_L and a high side switch element 103B_H. Further, the second inverter 100B includes three shunt resistors 100B_R. The shunt resistors are connected between the three low side switch elements included in the three legs and GND.

The number of shunt resistors is not limited to three for each inverter. For example, it is possible to use two shunt resistors for U phase and V phase, two shunt resistors for V phase and W phase, and two shunt resistors for U phase and W phase. The number of shunt resistors to be used and the arrangement of the shunt resistors are appropriately determined in consideration of product cost, design specifications and the like.

In power converter 1000, first inverter 100A and second inverter 100B can be electrically connected to power supply 500 and GND by first to

fourth switch elements

311, 312, 313 and 314, respectively. Specifically, the first switch element 311 switches connection / non-connection between the first inverter 100A and GND. The second switch element 312 switches connection / disconnection between the second inverter 100B and GND. The third switch element 313 switches connection / non-connection between the power supply 500 and the first inverter 100A. The fourth switch element 314 switches connection / disconnection between the power supply 500 and the second inverter 100B.

The first to

fourth switch elements

311, 312, 313 and 314 can block bidirectional current. As the first to

fourth switch elements

311, 312, 313 and 314, for example, semiconductor switches such as thyristors, analog switch ICs, or MOSFETs, and mechanical relays can be used. A combination of a diode and an IGBT may be used. In the present specification, the first to

fourth switch elements

311, 312, 313 and 314 may be denoted as

SWs

311, 312, 313 and 314, respectively. The

SWs

311, 312, 313 and 314 are described as MOSFETs.

The SW 311 is disposed such that forward current flows in the internal parasitic diode toward the first inverter 100A. The SW 312 is arranged such that forward current flows in the parasitic diode toward the second inverter 100B. The SW 313 is arranged such that forward current flows to the power supply 500 in the parasitic diode. The SW 314 is arranged such that forward current flows to the power supply 500 in the parasitic diode.

The power conversion device 1000 may further include fifth and

sixth switch elements

315 and 316 for reverse connection protection as illustrated. The fifth and

sixth switch elements

315, 316 are typically semiconductor switches of a MOSFET having parasitic diodes. The fifth switch element 315 is connected in series to the SW 313, and is disposed such that a forward current flows toward the first inverter 100A in the parasitic diode. The sixth switch element 316 is connected in series to the SW 314, and is disposed such that a forward current flows toward the second inverter 100B in the parasitic diode. Even when the power supply 500 is reversely connected, reverse current can be cut off by the two switch elements for reverse connection protection.

The number of switch elements to be used is not limited to the illustrated example, and is appropriately determined in consideration of design specifications and the like. Particularly in the on-vehicle field, high quality assurance is required from the viewpoint of safety, so it is preferable to provide a plurality of switch elements for each inverter.

The power supply 500 generates a predetermined power supply voltage (for example, 12 V). As the power supply 500, for example, a DC power supply is used. However, the power supply 500 may be an AC-DC converter or a DC-DC converter, or may be a battery.

As illustrated, the power supply 500 may be a single power supply common to the first inverter 100A and the second inverter 100B, or a first power supply for the first inverter 100A and a second power supply for the second inverter 100B. May be provided.

A coil 600 is provided between the power supply 500 and each inverter of the power conversion device 1000. The coil 600 functions as a noise filter, and smoothes high frequency noise included in the voltage waveform supplied to each inverter or high frequency noise generated in each inverter so as not to flow out to the power supply 500 side.

A capacitor (not shown) is connected to the power supply terminal of each inverter. The capacitor is a so-called bypass capacitor, which suppresses voltage ripple. The capacitor is, for example, an electrolytic capacitor, and the capacity and the number to be used are appropriately determined according to design specifications and the like.

The first peripheral circuit 400A is a circuit for controlling the driving of the first inverter 100A. The first peripheral circuit 400A includes, for example, a first predriver 420A, a first drive circuit 440A, and a first subdriver 450A.

The second peripheral circuit 400B is a circuit for controlling the driving of the second inverter 100B. Similar to the first peripheral circuit 400A, the second peripheral circuit 400B includes, for example, a second predriver 420B, a second drive circuit 440B, and a second subdriver 450B.

The second peripheral circuit 400B typically has substantially the same structure and function as the first peripheral circuit 400A. More specifically, the individual parts have substantially the same structure and function.

The controller 410 is an integrated circuit that controls the entire power conversion apparatus 1000, and is, for example, a microcontroller or a field programmable gate array (FPGA).

The controller 410 controls the first peripheral circuit 400A and the second peripheral circuit 400B. Specifically, the controller 410 controls the switching operation of the three low side switch elements and the three high side switch elements in each of the first inverter 100A and the second inverter 100B. For example, the controller 410 controls the first drive circuit 440A when the first pre-driver 420A fails, and controls the second drive circuit 440B when the second pre-driver 420B fails.

The controller 410 can control the target position, rotational speed, current, and the like of the rotor of the motor 200 to realize closed loop control. Therefore, the controller 410 typically includes an input port for inputting an output signal from the position sensor 700 that detects the position of the rotor.

The position sensor 700 is realized by, for example, a combination of an MR sensor having a resolver, a Hall IC, or a magnetoresistive (MR) element and a sensor magnet. Position sensor 700 detects the position of the rotor (hereinafter referred to as “rotation signal”), and outputs a rotation signal to controller 410.

The controller 410 may include an input port for inputting an output signal from the torque sensor 800, instead of or in addition to the input port for the position sensor 700. In this case, the controller 410 can control the target motor torque. In addition, the controller 410 can include, for example, a dedicated port for connecting to a vehicle-mounted control area network (CAN).

For example, two position sensors 700 and two torque sensors 800 (see FIG. 4) may be provided in consideration of sensor redundancy. If one of the two sensors fails, motor control can continue using the non-failing sensor.

The controller 410 can further include an input port for inputting a current signal output from the above-described current sensor. The controller 410 may receive a digital signal converted by an external AD (analog-digital) converter as an actual current value, or may receive an analog signal from the current sensor as it is and convert it into a digital signal inside the controller 410. You may

The controller 410 sets a target current value in accordance with the actual current value and the rotation signal of the rotor to generate a PWM (Pulse Width Modulation) signal, and outputs them to the first predriver 420A and the second predriver 420B. Further, in the present embodiment, the controller 410 outputs a control signal for controlling on / off of the SW 311 to the first sub driver 450A, and outputs a control signal for controlling on / off of the SW 312 to the second sub driver 450B. .

The predriver is also called a gate driver. General-purpose predrivers can be widely used as the first predriver 420A and the second predriver 420B.

The first predriver 420A is connected between the controller 410 and the first inverter 100A. The first pre-driver 420A generates control signals for controlling the switching operations of the three low-side switch elements and the three high-side switch elements in the first inverter 100A under the control of the controller 410, and controls these switch elements. give. Specifically, the first predriver 420A generates a control signal (gate control signal) for controlling the switching operation of each SW in the first inverter 100A in accordance with the PWM signal from the controller 410, and controls the gate of each SW. Give a signal.

The second predriver 420B is connected between the controller 410 and the second inverter 100B. The second pre-driver 420B generates control signals for controlling switching operations of the three low-side switch devices and the three high-side switch devices in the second inverter 100B under the control of the controller 410, and controls these switch devices. give. Specifically, the second pre-driver 420B generates a gate control signal for controlling the switching operation of each SW in the second inverter 100B in accordance with the PWM signal from the controller 410, and supplies the control signal to the gate of each SW.

The first pre-driver 410A can generate a voltage CP_Pr1 larger than the voltage of the power supply 500 (for example, 12 V). The second predriver 410B can generate a voltage CP_Pr2 larger than the voltage of the power supply 500. The boosted voltages CP_Pr1 and CP_Pr2 are, for example, 18 V or 24 V. Each predriver is a charge pump system.

In the present embodiment, the power supply circuit 430 is a power supply circuit common to the first peripheral circuit 400A and the second peripheral circuit 400B, and is, for example, a power supply IC. For example, 12V power is supplied from the power supply 500 to the power supply circuit 430. The power supply circuit 430 supplies the necessary power supply voltage to each block of the first peripheral circuit 400A and the second peripheral circuit 400B. Although power supply circuit 430 is shown in FIG. 1 as two functional blocks, it is not intended to be separate physically separate power supply circuits.

The power supply circuit 430 supplies a power supply voltage VCC of, for example, 5.0 V or 3.3 V to the controller 410, the first predriver 420A, and the second predriver 420B. In the present embodiment, the power supply circuit 430 can provide control signals for controlling the on / off of the

SWs

313, 314, 315 and 316 to them.

The power supply circuit 430 can generate a voltage CP_PM that is larger than the voltage of the power supply 500. The boosted voltage CP_PM is, for example, 18 V or 24 V.

In the present embodiment, a voltage larger than that of the power supply 500 is required. Therefore, as described above, such a large voltage is generated using the first predriver 420A, the second predriver 420B, and the power supply circuit 430. There may be at least one block for boosting the voltage of the power supply 500 in each peripheral circuit.

Here, before describing the first drive circuit 440A and the second drive circuit 440B, gate control signals generated by the first predriver 420A and the second predriver 420B will be described. The gate control signal will be described below by taking the first predriver 420A as an example.

In the present specification, control of the power conversion device 1000 when no failure occurs in the power conversion device 1000 is referred to as “control at normal time”, and control when a failure occurs is “control at abnormal time”.
It shall be written as

In normal control, the

switches

311, 312, 313, 314, 315 and 316 are in the on state. Therefore, the potential of the node NA_L connecting the SWs 101A_L, 102A_L and 103A_L in the first inverter 100A is the GND potential. Therefore, the reference potentials of the gates of the SW 101A_L, 102A_L, and 103A_L, that is, the source potentials are low. In that case, the voltage level of the gate control signal applied to the gate of SW may be relatively low, and it is possible to control the switching operation of the low side switch element without any problem. Hereinafter, the voltage of the gate control signal may be referred to as “gate voltage”.

On the other hand, the reference potentials of the three SWs 101A_H, 102A_H and 103A_H of the first inverter 100A are the potentials of the nodes NA_1, NA_2 and NA_3 between the low side switch element and the high side switch element, that is, the windings M1 and M2 of each phase. And the drive voltage supplied to M3 are high. In order to turn on the high side switch element, it is necessary to apply a gate voltage higher than the gate voltage applied to the low side switch element to the high side switch element.

As described above, the first pre-driver 420A can boost a voltage of, for example, 12 V to generate a voltage of 18 V, and can apply high voltages to the SW 101A_H, 102A_H, and 103A_H. As a result, it becomes possible to properly turn on the high side switch element in the switching operation. As described above, the first pre-driver 420A applies a gate voltage higher than the gate voltage applied to the low-side switch element to the high-side switch element in normal control. The gate voltage applied to the low side switch element is 12 V, for example, and the gate voltage applied to the high side switch element is 18 V, for example.

A case where a failure occurs in the power converter 1000 will be considered. "Failure" mainly refers to a failure that occurs in the peripheral circuit. The occurrence of a failure on the first inverter 100A side of the motor 200 means that a failure occurs in the first peripheral circuit 400A, and more specifically, for example, the first predriver 420A fails and becomes inoperable It means that. The occurrence of a failure on the second inverter 100B side means that a failure occurs in the second peripheral circuit 400B, and more specifically, for example, the failure of the second predriver 420B to render it inoperable Do.

For example, it is assumed that the first predriver 420A fails. In that case, naturally, the first predriver 420A can not drive the first inverter 100A under the control of the controller 410. However, if the low side node NA_L in the first inverter 100A can be made to function as a neutral point, driving of the motor 200 can be continued by driving the second inverter 100B using this neutral point.

In the present embodiment, for example, when the first predriver 420A fails, the node NA_L on the low side of the first inverter 100A functions as a neutral point. At this time, the controller 410 turns off the first switch element 311 so that current control can be appropriately performed. Thus, the neutral point is electrically disconnected from GND. As a result, the potential of the node NA_L on the low side is not the GND potential and is higher than the potential. In other words, the reference potentials of the gates of SW101A_L, 102A_L and 103A_L are in a floating state. In this state, when a gate voltage of the same magnitude as the gate voltage (for example, 12 V) in the normal control is applied to the low side switch element, the gate-source voltage becomes smaller than that in the normal control.

As the gate-source voltage decreases, the on-resistance value between the source and the drain of the SW 101A_L, 102A_L, and 103A_L may increase, or the SW 101A_L, 102A_L, and 103A_L may be unintentionally turned off. In order to cause the node NA_L on the low side of the first inverter 100A to function as a neutral point, the switches SW101A_L, 102A_L, and 103A_L need to be properly turned on. Therefore, the gate voltages applied to the switches SW101A_L, 102A_L and 103A_L need to be larger than those in the normal control.

In view of the problems described above, the power conversion device 1000 according to the present disclosure includes a first drive circuit 440A and a second drive circuit 440B. Since the circuit structure and function of the second drive circuit 440B are substantially the same as those of the first drive circuit 440A, the circuit structure and function will be mainly described below by taking the first drive circuit 440A as an example.

The first drive circuit 440A is connected to the three low side switch elements of the first inverter 100A. The first drive circuit 440A is a dedicated drive circuit for constantly turning on the switches 101A_L, 102A_L and 103A_L in the first inverter 100A when a failure occurs on the first inverter 100A side of the motor 200. The low side node NA_L of the first inverter 100A can be appropriately functioned as a neutral point by the first drive circuit 440A.

The second drive circuit 440B is connected to the three low-side switch elements of the second inverter 100B. The second drive circuit 440B is a dedicated drive circuit for constantly turning on the switches 101B_L, 102B_L and 103B_L in the second inverter 100B when a failure occurs on the second inverter 100B side of the motor 200. By the second drive circuit 440B, the node NB_L on the low side of the second inverter 100B can be appropriately functioned as a neutral point.

In normal control, the gate control signal of the low side switch element is supplied from the first predriver 420A to the switches 101A_L, 102A_L, and 103A_L. In the control at the time of abnormality, the gate control signal is supplied from the first drive circuit 440A to the SW 101A_L, 102A_L, and 103A_L.

The voltage level of the control signal that the first drive circuit 440A gives to the three low side switch elements of the first inverter 100A is larger than the voltage level of the control signal that the first predriver 420A gives to those low side switch elements. In the present embodiment, the voltage levels of the control signals that the first drive circuit 440A gives to the three low side switch elements of the first inverter 100A are the same as those of the first predriver 420A for the three high side switch elements of the first inverter 100A. Equal to the voltage level of the control signal to be given. The gate voltage is, for example, 18V.

The voltage level of the control signal that the second drive circuit 440B gives to the three low side switch elements of the second inverter 100B is larger than the voltage level of the control signal that the second predriver 420B gives to those low side switch elements. In this embodiment, the voltage level of the control signal that the second drive circuit 440B gives to the three low-side switch elements of the second inverter 100B is the same as that of the second pre-driver 420B for the three high-side switch elements of the second inverter 100B. Equal to the voltage level of the control signal to be given. The gate voltage is, for example, 18V.

When a failure occurs on the second inverter 100B side of the motor 200, the first power supply voltage generated on the first inverter 100A side is supplied to the second drive circuit 440B. The voltage generated on the side of the first inverter 100A means the power supply voltage generated in the first peripheral circuit 400A. For example, the first power supply voltage is the boosted voltage CP_Pr1 generated by the first predriver 420A. The magnitude of the first power supply voltage is greater than the voltage of the power supply 500, for example 18V.

When a failure occurs on the first inverter 100A side, the second power supply voltage generated on the second inverter 100B side is supplied to the first drive circuit 440A. The voltage generated on the second inverter 100B side means the power supply voltage generated in the second peripheral circuit 400B. For example, the second power supply voltage is the boosted voltage CP_Pr2 generated by the second predriver 420B. The magnitude of the second power supply voltage is greater than the voltage of the power supply 500, for example 18V. In the present embodiment, the magnitude of the first power supply voltage is equal to the magnitude of the second power supply voltage.

Each of the first power supply voltage and the second power supply voltage may be the boosted voltage CP_PM generated by the power supply circuit 430. For example, when the first pre-driver 420A fails, the boosted voltage CP_PM can be supplied to the first drive circuit 440A as the second power supply voltage. For example, if the second predriver 420B fails, the second drive circuit 440B may be supplied with the boosted voltage CP_PM as a first power supply voltage.

When a failure occurs on the first inverter 100A side of the motor 200, the first drive circuit 440A supplies a second power supply voltage to turn on a control signal to turn on the three low-side switch elements of the first inverter 100A. It applies to those low side switch elements. When a failure occurs on the second inverter 100B side, the second drive circuit 440B supplies the first power supply voltage to turn on the low-side switch elements of the second inverter 100B for controlling the low-side switches. Give to the switch element.

FIG. 2A schematically shows a functional block of the first drive circuit 440A, and FIG. 2B schematically shows a functional block of the second drive circuit 440B.

The second power supply voltage is supplied as the power supply voltage 443 to the first drive circuit 440A. The second power supply voltage is, for example, boosted voltage CP_Pr2. The first power supply voltage is supplied as a power supply voltage 443 to the second drive circuit 440B. The first power supply voltage is, for example, boosted voltage CP_Pr1. It should be noted that the power supply voltage 443 is set so that the gate-source voltage of the low side switch element does not become larger than the withstand voltage.

Each of the first drive circuit 440A and the second drive circuit 440B has

switches

441 and 442. In normal control, the

switches

441 and 442 are off.

When a failure occurs on the first inverter 100A side of the motor 200, the controller 410 turns on the switch 441 of the first drive circuit 440A. As a result, the power supply voltage 443 is applied as the gate voltage to the three low side switch elements of the first inverter 100A. All three low side switch elements are turned on, and the low side node NA_L of the first inverter 100A can function as a neutral point.

For example, when a failure occurs in the power converter 1000, the operation of the power converter 1000 may be forcibly stopped. In that case, the controller 410 turns on the switch 442. Since the GND potential is applied to the low side switch element as a gate voltage, the three low side switch elements are turned off. However, the switch 442 is optional, and may not be in the drive circuit, for example, when the forced stop is not required.

FIG. 3 schematically illustrates the block configuration of the first drive circuit 440A in the first peripheral circuit 400A. The switch element 315 is not shown in FIG.

The first drive circuit 440 A includes a plurality of

switch elements

10, 11, 12, 13, 20, 21, 22 and 23 of the open collector output system. In the illustrated example, the

switch elements

11, 12, 13 and 20 are PNP bipolar transistors. The

switch elements

10, 21, 22 and 23 are NPN bipolar transistors. A push-pull circuit is connected via a resistor to a gate control signal line for controlling the low side switch element of each phase. The

switches

441 and 442 may be configured by a combination of a plurality of

transistors

10, 11, 12, 13, 20, 21, 22, 23 and a plurality of resistors.

When controller 410 pulls transistor 20,

transistors

21, 22 and 23 are pushed. As a result, the gate potentials of the switches SW101A_L, 102A_L and 103A_L in the first inverter 100A become low levels corresponding to the GND potential. On the other hand, when the controller 410 pushes the transistor 10, the

transistors

11, 12 and 13 are pulled and the gate potentials of the SW 101A_L, 102A_L and 103A_L become high level corresponding to the power supply voltage 463.

Between the source and the gate of the SW 101A_L, 102A_L and 103A_L,

protection circuits

31, 32, 33 in which a resistor and a diode are connected in parallel are connected. Between the source and the gate of SW101A_H, 102A_H and 103A_H,

protection circuits

41, 42 and 43 in which a resistor and a diode are connected in parallel are connected.

Power converter 1000 can include first and second protection circuits. The first protection circuit has

protection circuits

51, 52 and 53. The protection circuit 51 is preferably connected between an output terminal (not shown) of the first predriver 420A connected to the gate of the SW 101A_L and the GND. Similarly, the protection circuit 52 is connected between the output terminal (not shown) of the first predriver 420A connected to the gate of the SW 102A_L and GND, and the first predriver connected to the gate of the SW 103A_L. It is preferable to connect a protection circuit 53 between the output terminal (not shown) of 420 A and GND. Similarly, it is preferable to provide a second protection circuit having three protection circuits on the second inverter 100 B side of the motor 200 as well.

When a control signal for turning on the three low-side switch elements is output from the first drive circuit 440A to the first inverter 100A, each of the

protection circuits

51, 52, and 53 has a specified value (withstand voltage) for the first predriver 420A. ) Suppress the input of signals of the above voltage levels. The withstand voltage here is, for example, the withstand voltage of the circuit element in the first pre-driver 420A that outputs the gate control signal for the SW 101A_L, 102A_L and 103A_L in the normal control.

The

protection circuits

51, 52, 53 are, for example, zener diodes. The

protection circuits

51, 52, and 53 function when the voltage of the gate control signal output from the first drive circuit 440A is close to or higher than the withstand voltage. For example, in the case where the withstand voltage is 18 V, the

protection circuits

51, 52, and 53 function when the voltage of the gate control signal becomes 17 V or more. Thereby, the voltage supplied to the output terminal of the first predriver 420A can be made smaller than the withstand voltage. In the present embodiment, a gate voltage higher than that in the normal control is supplied to the SW 101A_L, 102A_L, and 103A_L. Even if the high gate voltage unintentionally exceeds the withstand voltage, the

protection circuits

51, 52 and 53 can protect the first predriver 420A.

According to the first drive circuit 440A, gate voltages higher than those in the normal control can be supplied to the SWs 101A_L, 102A_L, and 103A_L. By raising the gate voltage, it is possible to suppress a decrease in the gate-source voltage even if the source potential becomes a potential at a neutral point. While being able to suppress that the ON-resistance value between source-drain of SW101A_L, 102A_L, and 103A_L becomes large, it can suppress that SW101A_L, 102A_L, and 103A_L turn off unintentionally.

Power converter 1000 includes a ROM (not shown). The ROM is, for example, a writable memory (for example, a PROM), a rewritable memory (for example, a flash memory), or a read only memory. The ROM stores a control program including instructions for causing the controller 410 to control the power conversion apparatus 1000. For example, the control program is temporarily expanded in a RAM (not shown) at boot time.

Hereinafter, points to be noted about power supply wiring and signal wiring of a circuit board (for example, printed circuit board) on which each component of power conversion device 1000 is mounted will be described.

The second power supply voltage generated on the second inverter 100B side of the motor 200 is supplied to the first drive circuit 440A. The first power supply voltage generated on the side of the first inverter 100A of the motor 200 is supplied to the second drive circuit 440B. Therefore, the first power supply wiring and the second power supply wiring are provided on the circuit board. For example, the first power supply wiring is a power supply wiring for supplying a first power supply voltage from the first pre-driver 420A or the power supply circuit 430 to the second drive circuit 440B. For example, the second power supply wiring is a power supply wiring for supplying a second power supply voltage from the second predriver 420B or the power supply circuit 430 to the first drive circuit 440A.

The controller 410 may be communicably connected to the power supply circuit 430. The communication may be realized using serial communication such as I ² C, for example. Thus, the power supply circuit 430 can detect an abnormal operation of the controller 410. When the power supply circuit 430 detects the abnormal operation, the power supply circuit 430 can provide a reset signal to restart the controller 410. Furthermore, the controller 410 can monitor failures of the first predriver 420A and the second predriver 420B. For example, such monitoring may be realized by transmitting the status of the pre-driver, specifically, a status signal indicating a failure, from each pre-driver to the controller 410 periodically or at the timing when the failure occurs.

For example, when the controller 410 detects a failure on the second inverter 100B side of the motor 200, the controller 410 may instruct the second drive circuit 440B to start driving. The second drive circuit 440B can provide control signals for turning on the three low-side switch elements of the second inverter 100B to the low-side switch elements in response to the instruction to start the drive.

For example, when the controller 410 detects a failure on the first inverter 100A side of the motor 200, the controller 410 may instruct the first drive circuit 440A to start driving. The first drive circuit 440A can provide control signals for turning on the three low-side switch elements of the first inverter 100A to the low-side switch elements in response to the instruction to start the drive.

Thus, by driving the drive circuit in response to an instruction from the controller 410, the drive circuit can be appropriately driven only when a failure occurs. As a result, power consumption can be reduced as compared with always driving the drive circuit.

A modification of the present embodiment will be described with reference to FIGS. 4 and 5.

FIG. 4 schematically shows a block configuration example of a power conversion device 1000 according to a modification of the present embodiment.

Power conversion device 1000 according to this modification is different from power conversion device 1000 shown in FIG. 1 in that power conversion device 1000 according to this modification does not include first predriver 420A and second predriver 420B. At this time, the controller 410 may incorporate a pre-driver.

Motor driving generally requires a large voltage and current to drive switch elements (power elements) of the inverter. The predriver is used as a circuit for converting the PWM control signal from the controller into a high voltage and high current signal. In other words, a low voltage drivable motor does not necessarily require a pre-driver. Therefore, the function of the predriver can be implemented in the controller. In the present disclosure, in power converter 1000 supplying power to low-voltage drivable motor 200, controller 410 may incorporate a pre-driver. In that case, the controller 410 can directly control the first inverter 100A and the second inverter 100B.

As shown in FIG. 4, as the power supply circuit, the first power supply circuit 430A may be provided in the first peripheral circuit 400A, and the second power supply circuit 430B may be provided in the second peripheral circuit 400B. The first power supply circuit 430A and the second power supply circuit 430B are separate power supply circuits. The first power supply circuit 430A can boost the voltage of the power supply 500 to generate a voltage CP_PM1, and the second power supply circuit 430B can boost the voltage of the power supply 500 to generate a voltage CP_PM2.

The boosted voltage CP_PM1 may be supplied as a first power supply voltage from the first power supply circuit 430A to the second drive circuit 440B, and the boosted voltage CP_PM2 may be supplied as a second power supply voltage from the second power supply circuit 430B to the first drive circuit 440A. . The power supply voltage VCC may be supplied to the controller 410 from the first power supply circuit 430A or the second power supply circuit 430B.

Thus, by providing two power supply circuits, for example, even if the first power supply circuit 430A fails, the second power supply circuit 430B can continue to supply the power supply voltage VCC to the controller 410. As a result, the controller 410 can continuously control the switching operation of the switch element of the second inverter 100B. Furthermore, by supplying the boosted voltage CP_PM2 of the second power supply circuit 430B to the first drive circuit 440A, the node NA_L on the low side of the first inverter 100A can function as a neutral point. Control using a neutral point will be described in detail later.

5A and 5B schematically show a further exemplary block configuration of a power conversion device 1000 according to a modification of the present embodiment. Power conversion device 1000 according to this modification differs from power conversion device 1000 shown in FIG. 1 in that power conversion device 1000 further includes a first booster circuit 460A and a second booster circuit 460B or a single booster circuit 460.

In this embodiment, an example in which the first power supply voltage is generated by at least one of the first predriver 420A and the power supply circuit 430 and the second power supply voltage is generated by at least one of the second predriver 420B and the power supply circuit 430 is described. explained. The power conversion device 1000 according to the present modification includes a booster circuit that generates the first power supply voltage and the second power supply voltage and is different from the power supply circuit and the predriver.

As shown in FIG. 5A, a single boost circuit 460 may be connected to the controller 410. The booster circuit 460 boosts the voltage of the power supply 500 to generate a voltage CP_PV. The boosted voltage CP_PV is, for example, 18V. In this modification, boosted voltage CP_PV is supplied as a first power supply voltage from booster circuit 460 to second drive circuit 440B, and boosted voltage CP_PV is supplied as a second power supply voltage from booster circuit 460 to first drive circuit 440A. obtain.

As shown in FIG. 5B, two booster circuits may be connected to the controller 410. The first booster circuit 460A is provided in the first peripheral circuit 400A, and boosts the voltage of the power supply 500 to generate a voltage CP_PV1. The second booster circuit 460B is provided in the second peripheral circuit 400B, and boosts the voltage of the power supply 500 to generate a voltage CP_PV2. The boosted voltages CP_PV1 and CP_PV2 are, for example, 18V. In this modification, the boosted voltage CP_PV1 may be supplied to the second drive circuit 440B as a first power supply voltage, and the boosted voltage CP_PV2 may be supplied to the first drive circuit 440A as a second power supply voltage.

[1-2. Operation of Power Conversion Device 1000 First, a specific example of a control method of the power conversion device 1000 when it is normal will be described. At normal times, none of power conversion device 1000 and three-phase windings M1, M2 and M3 of motor 200 have failed.

The controller 410 outputs a control signal to turn on the SW 311 to the first sub driver 450A, and outputs a control signal to turn on the SW 312 to the second sub driver 450B. The power supply circuit 430 (see FIG. 1) outputs a control signal to turn on the

SWs

313, 314, 315, and 316.

The

SWs

311, 312, 313, 314, 315 and 316 are all turned on. The power supply 500 and the first inverter 100A are electrically connected, and the power supply 500 and the second inverter 100B are electrically connected. Further, the first inverter 100A and GND are electrically connected, and the second inverter 100B and GND are electrically connected. In this connection state, the controller 410 outputs a PWM signal for controlling the switching operation of the switch elements of the first inverter 100A and the second inverter 100B to the first predriver 420A and the second predriver 420B. By switching the switch elements of the first inverter 100A and the second inverter 100B, it becomes possible to energize the three-phase windings M1, M2 and M3 to drive the motor 200. In the present specification, energization of a three-phase winding may be referred to as “three-phase energization control”.

FIG. 6 exemplifies a current waveform (sine wave) obtained by plotting current values flowing in U-phase, V-phase and W-phase windings of motor 200 when power converter 1000 is controlled in accordance with three-phase energization control. doing. The horizontal axis indicates the motor electrical angle (deg), and the vertical axis indicates the current value (A). In the current waveform of FIG. 6, current values are plotted every 30 ° of electrical angle. I _pk represents the maximum current value (peak current value) of each phase.

Table 1 shows the current value flowing to each inverter for each electrical angle in the sine wave of FIG. Specifically, Table 1 shows current values at every electrical angle of 30 ° flowing through the nodes NA_1, NA_2 and NA_3 (see FIG. 1) of the first inverter 100A, and the nodes NB_1, NB_2 and the second inverter 100B. The electric current value for every electrical angle of 30 degrees which flows through NB_3 (refer FIG. 1) is shown. Here, for the first inverter 100A, the current direction flowing from the first inverter 100A to the second inverter 100B is defined as a positive direction. The direction of the current shown in FIG. 6 follows this definition. Further, for the second inverter 100B, the current direction flowing from the second inverter 100B to the first inverter 100A is defined as a positive direction. Therefore, the phase difference between the current of the first inverter 100A and the current of the second inverter 100B is 180 °. In Table 1, the magnitude of the current value _{I 1} is ^{[(3) 1/2} / 2] _* is _{I pk,} the magnitude of the current value _{I 2} is _{I pk} / 2.

In the current waveform shown in FIG. 6, the sum of the currents flowing in the three-phase winding considering the direction of the current is “0” for each electrical angle. However, according to the circuit configuration of power conversion apparatus 1000, the currents flowing through the three-phase windings can be controlled independently, so it is also possible to perform control such that the sum of the currents does not become "0". For example, the controller 410 outputs a PWM signal for obtaining the current waveform shown in FIG. 6 to the first predriver 420A and the second predriver 420B.

Next, a specific example of a control method at the time of abnormality of the power conversion device 1000 will be described by taking a case where a failure occurs in the first peripheral circuit 400A as an example. The control method described below is applied also when a failure occurs in the second peripheral circuit 400B.

As an example, consider the case where the first predriver 420A fails in the first peripheral circuit 400A. Since the first pre-driver 420A has a failure, although the first inverter 100A does not have a failure, three-phase energization control can not be performed under normal control.

When the controller 410 detects a failure of the first pre-driver 420A, it switches control of the motor 200 from normal control to abnormal control. The controller 410 instructs the first drive circuit 440A to start driving. For example, since the second power supply voltage is supplied from the second predriver 420B to the first drive circuit 440A, a failure of the first predriver 420A does not affect the first drive circuit 440A.

In response to the instruction to start driving from the controller 410, the first drive circuit 440A applies a control signal to them to turn on the SWs 101A_L, 102A_L and 103A_L of the first inverter 100A. The controller 410 outputs a control signal to turn off the SW 311 to the first sub driver 450A. As a result, the SW 311 is turned off, and the first inverter 100A is electrically disconnected from the GND. The switches 101A_L, 102A_L and 103A_L are always in the on state, and the low side node NA_L of the first inverter 100A can function as a neutral point. At this time, the switches SW101A_H, 102A_H and 103A_H of the first inverter 100A are in the OFF state. The

switch elements

313 and 315 may be in the on state or in the off state, but are preferably in the off state.

FIG. 7 exemplifies the state of current flowing to two inverters at an electrical angle of 270 ° of the current waveform shown in FIG.

The controller 410 can continue the three-phase conduction control using the neutral point of the first inverter 100A by outputting the PWM signal to the second predriver 420B. For example, the controller 410 can energize the windings M1, M2 and M3 by outputting a PWM signal for obtaining the current waveform shown in FIG. 6 to the switch element of the second inverter 100B.

According to the present embodiment, even if the first pre-driver 420A fails, the second power supply voltage is supplied to the first drive circuit 440A, so three-phase conduction control using the neutral point can be continued. It becomes possible.

As another example, it is possible to replace power supply circuit 430 in the configuration shown in FIG. 1 with two first power supply circuits 430A and second power supply circuit 430B shown in FIG. In such a case, if the first power supply circuit 430A fails, the power supply voltage VCC can not be supplied to the first predriver 420A, and it becomes impossible to drive the first inverter 100A.

According to the present embodiment, for example, the boosted voltage CP_PM2 generated by the second power supply circuit 430B or the boosted voltage CP_Pr2 generated by the second predriver 420B can be supplied to the first drive circuit 440A. Therefore, the first drive circuit 440A can give them a control signal to turn on the SWs 101A_L, 102A_L and 103A_L of the first inverter 100A without being affected by the failure of the first power supply circuit 430A.

Second Embodiment FIG. 8 schematically shows a block configuration of a motor module 2000A according to the present embodiment and mainly shows a block configuration of a power conversion apparatus 1000A. FIG. 9 schematically shows the drive circuit 440 and functional blocks around it.

Power conversion device 1000A differs from power conversion device 1000 according to the first embodiment in that power conversion device 1000A includes a drive circuit 440 common to first inverter 100A and second inverter 100B. The differences from the first embodiment will be mainly described below.

The power conversion device 1000A includes a drive circuit 440 common to the first inverter 100A and the second inverter 100B, a first switch 900, and a second switch 910.

The drive circuit 440 is connected to the three low side switch elements of the first inverter 100A and the three low side switch elements of the second inverter 100B. When a failure occurs on the first inverter 100A side of the motor 200, the drive circuit 440 supplies control signals for turning on the three low-side switch elements of the first inverter 100A by supplying the second power supply voltage. A control signal for turning on the three low-side switch elements of the second inverter 100B is supplied to the low-side switch elements and supplying a first power supply voltage when a failure occurs on the second inverter 100B side. Apply to the low side switch element.

Similar to the first drive circuit 440A or the second drive circuit 440B according to the first embodiment, the drive circuit 440 includes

switches

441 and 442, and can be configured from a plurality of open collector output type transistors and a plurality of resistors. Drive circuit 440 is controlled by controller 410.

For example, it is assumed that a failure occurs on the first inverter 100A side, that is, in the first peripheral circuit 400A. For example, when receiving a status signal indicating a failure from the first pre-driver 420A, the controller 410 starts control of the drive circuit 440.

The first switch 900 supplies the first power supply voltage as the power supply voltage 443 to the drive circuit 440 and supplies the second power supply voltage as the power supply voltage 443 to the drive circuit 440 under the control of the controller 410. Switch. When detecting the failure of the first pre-driver 420A, the controller 410 controls the first switch 900 to determine to supply the second power supply voltage (for example, CP_Pr2) as the power supply voltage 443 to the drive circuit 440.

The second switch 910 supplies the output of the drive circuit 440 from the drive circuit 440 to the three low-side switch elements of the first inverter 100A, and the three low-side switch elements of the drive circuit 440 to the second inverter 100B. The supply of the output is switched under the control of the controller 410. When the controller 410 detects a failure in the first pre-driver 420A, it controls the second switch 910 to determine to supply the output of the drive circuit 440 to the three low-side switch elements of the first inverter 100A.

According to the present embodiment, as in the first embodiment, even if a failure occurs in the first peripheral circuit 400A or the second peripheral circuit 400B, the three-phase conduction control using the neutral point in one of the inverters is continued It is possible to Furthermore, the common drive circuit 440 is used for the first inverter 100A and the second inverter 100B, which is advantageous in terms of circuit area and cost.

The drive circuit 440 may be an integrated circuit in which the first drive circuit 440A and the second drive circuit 440B according to the first embodiment are integrated into one chip. Such circuit forms are also within the scope of the present disclosure.

Third Embodiment FIG. 10 schematically shows a typical configuration of an electric power steering apparatus 3000 according to the present embodiment.

Vehicles such as automobiles generally have an electric power steering (EPS) device. The electric power steering apparatus 3000 according to the present embodiment has a steering system 520 and an auxiliary torque mechanism 540 that generates an auxiliary torque. Electric power steering apparatus 3000 generates an assist torque that assists the steering torque of the steering system generated by the driver operating the steering wheel. The assist torque reduces the burden on the driver's operation.

The steering system 520 includes, for example, a steering handle 521, a steering shaft 522,

free shaft joints

523A and 523B, a rotating shaft 524, a rack and pinion mechanism 525, rack shafts 526, left and right ball joints 552A and 552B,

tie rods

527A and 527B,

knuckles

528A, 528B, and left and

right steering wheels

529A, 529B.

The auxiliary torque mechanism 540 includes, for example, a steering torque sensor 541, an electronic control unit (ECU) 542 for a car, a motor 543, and a reduction mechanism 544. The steering torque sensor 541 detects a steering torque in the steering system 520. The ECU 542 generates a drive signal based on a detection signal of the steering torque sensor 541. The motor 543 generates an auxiliary torque corresponding to the steering torque based on the drive signal. The motor 543 transmits the generated assist torque to the steering system 520 via the reduction mechanism 544.

The ECU 542 includes, for example, a first peripheral circuit 400A and a second peripheral circuit 400B according to the first embodiment. In automobiles, an electronic control system is built around an ECU. In the electric power steering apparatus 3000, for example, a motor drive unit is constructed by the ECU 542, the motor 543 and the inverter 545. The

motor module

2000, 2000A by

Embodiment

1 and 2 can be used suitably for the unit.

Embodiments of the present disclosure can be widely used in a variety of devices equipped with various motors, such as vacuum cleaners, dryers, ceiling fans, washing machines, refrigerators, and electric power steering devices.

100A: first inverter 100B: second inverter 200:

motor

311, 312, 313, 314, 315, 316: switch element 400A: first peripheral circuit 400B: second peripheral circuit 410: controller 420A: first predriver 420B: Second pre-driver 430: power supply circuit 430A: first power supply circuit 430B: second power supply circuit 440A: first drive circuit 440B; second drive circuit 450A: first subdriver 450B: second subdriver 460: boost circuit 460A: First booster circuit 460B:

second booster circuit

1000, 1000A: power converter 2000, 000A: Motor Module 3000: electric power steering system

Claims

A power converter that converts power from a power supply into power supplied to a motor having n-phase (n is an integer of 3 or more) windings,

A first inverter connected to one end of a winding of each phase of the motor, the first inverter comprising n legs each having a low side switch element and a high side switch element;

A second inverter connected to the other end of the winding of each phase, the second inverter comprising n legs each having a low side switch element and a high side switch element;

A driving circuit connected to the n low-side switching devices of the first inverter and the n low-side switching devices of the second inverter,

When a failure occurs on the first inverter side of the motor, a control signal is provided to the n low side switch elements to turn on the n low side switch elements of the first inverter,

A drive circuit which gives a control signal for turning on the n low-side switch elements of the second inverter to the n low-side switch elements when a failure occurs on the second inverter side of the motor;

A control circuit that controls switching operations of the n low-side switch elements and the n high-side switch elements in each of the first inverter and the second inverter, and controls the drive circuit;

When a failure occurs on the second inverter side of the motor, a first power supply voltage generated on the first inverter side of the motor is supplied to the drive circuit, and on the first inverter side of the motor A power converter, wherein a second power supply voltage generated on the second inverter side of the motor is supplied to the drive circuit when a failure occurs.
The drive circuit is connected to the n low-side switch elements of the first inverter and supplies the second power supply voltage when a failure occurs on the first inverter side of the motor. A first drive circuit for providing the n low-side switch elements with the control signal to turn on the n low-side switch elements of the first inverter;

It is connected to the n low-side switch elements of the second inverter, and when a failure occurs on the second inverter side of the motor, the first power supply voltage is supplied to the second inverter. and a second drive circuit that applies the control signal to turn on the n low-side switch elements to the n low-side switch elements, and the control circuit controls the first drive circuit and the second drive circuit. The power converter device according to claim 1.
A control signal for controlling the switching operation of the n low-side switch elements and the n high-side switch elements in the first inverter is generated under the control of the first control circuit, and the n low-side switch elements And a first predriver given to the n high side switch elements,

A control signal for controlling the switching operation of the n low-side switching devices and the n high-side switching devices in the second inverter is generated under the control of the second control circuit, and the n low-side switching devices The power conversion device according to claim 2, further comprising: and a second predriver that supplies the n high-side switch elements.
The first drive voltage generated by the first predriver is supplied to the second drive circuit.

The second power supply voltage generated by the second predriver is supplied to the first drive circuit.

The power conversion device according to claim 3, wherein the first power supply voltage is larger than a voltage of the power supply, and the second power supply voltage is larger than a voltage of the power supply.
The power conversion device according to claim 4, further comprising a power supply circuit that supplies a power supply voltage to the control circuit, the first predriver and the second predriver.
A first power supply line for supplying the first power supply voltage from the first predriver to the second drive circuit;

The power conversion device according to any one of claims 3 to 5, further comprising: a second power supply wiring for supplying the second power supply voltage from the second predriver to the first drive circuit.
The semiconductor device further comprises a booster circuit that boosts the voltage of the power supply to generate the first power supply voltage and the second power supply voltage.

The first power supply voltage and the second power supply voltage are greater than the voltage of the power supply,

The power conversion device according to claim 3, wherein the first power supply voltage is supplied from the booster circuit to the second drive circuit, and the second power supply voltage is supplied from the booster circuit to the first drive circuit.
The power supply circuit further includes a power supply circuit that supplies a power supply voltage to the control circuit, the first predriver, and the second predriver.

The first drive circuit is supplied with the second power supply voltage generated by the power supply circuit, and the second drive circuit is supplied with the first power supply voltage generated by the power supply circuit.

The power conversion device according to claim 3, wherein the first power supply voltage is larger than a voltage of the power supply, and the second power supply voltage is larger than a voltage of the power supply.
The power converter according to any one of claims 1 to 8, wherein the magnitude of the first power supply voltage is equal to the magnitude of the second power supply voltage.
The power conversion device according to claim 5, wherein the control circuit and the power supply circuit are communicably connected to each other.
When the control circuit detects a failure on the second inverter side of the motor, the control circuit instructs the second drive circuit to start driving, and the second drive circuit responds to the command to start the drive. Providing the n low side switch elements with the control signal to turn on the n low side switch elements of the second inverter;

When the control circuit detects a failure on the first inverter side of the motor, the control circuit instructs the first drive circuit to start driving, and the first drive circuit responds to the command to start the drive. The power conversion device according to claim 10, wherein the control signal for turning on the n low-side switch elements of the first inverter is provided to the n low-side switch elements.
A first switch element for switching connection / disconnection between the first inverter and the ground;

A second switch element for switching connection / disconnection between the second inverter and the ground;

A third switch element for switching connection / disconnection between the first inverter and the power supply;

A fourth switch element for switching connection / disconnection between the second inverter and the power supply;

The power converter according to any one of claims 1 to 11, further comprising:
The voltage level of the control signal applied to the n low side switches of the first inverter by the first drive circuit is the voltage level of the control signal applied to the n low side switches of the first inverter by the first predriver. Greater than

The voltage level of the control signal that the second drive circuit gives to the n low side switches of the second inverter is the voltage level of the control signal that the second predriver gives to the n low side switches of the second inverter The power converter according to any one of claims 3, 4, 5, 6, 7, 8, 10, which is larger than the above.
The voltage level of the control signal applied to the n low side switches of the first inverter by the first drive circuit is the voltage of the control signal applied to the n high side switches of the first inverter by the first predriver. Equal to the level,

The voltage level of the control signal that the second drive circuit applies to the n low side switches of the second inverter is the voltage of the control signal that the second predriver applies to the n high side switches of the second inverter. The power converter according to any one of claims 3, 4, 5, 6, 7, 8, 10, which is equal to the level.
The power converter according to claim 13, wherein each of the first drive circuit and the second drive circuit comprises a plurality of transistors of an open collector output system.
When a control signal for turning on the n low-side switch elements is output from the first drive circuit to the first inverter, a signal having a voltage level higher than or equal to a specified value is input to the first predriver. A first protection circuit to suppress

When a control signal for turning on the n low-side switch elements is output from the second drive circuit to the second inverter, a signal having a voltage level higher than or equal to a specified value is input to the second predriver. A second protection circuit to suppress

The power conversion device according to any one of claims 13 to 15, further comprising:
The power converter according to claim 16, wherein each of the first protection circuit and the second protection circuit comprises a Zener diode.
The switch according to claim 1, further comprising: a switch configured to switch the supply of the first power supply voltage to the drive circuit and the supply of the second power supply voltage to the drive circuit under control of the control circuit. Power converter.
The motor,

The power converter according to any one of claims 1 to 18,

, A motor module.
An electric power steering apparatus comprising the motor module according to claim 19.